Hen party gift

Hi all, I'm going to my SiL-to-be's hen do in a few weeks and we've been asked to take a small gift for the hen which is 'in the spirit of a hen party'.

Now, as she's about to marry by brother, giving any of the usual sex-related tat gifts feels a little awkward! As does underwear (we've all been given her sizes by the bridesmaids, not sure she'll appreciate that though!!).

Any thoughts or inspiration?

I've already got her a lovely book (personal links) as part of a wedding gift so want to give her something fun but original (ie not 'just married' flip flops) for the hen do.

Ok my bridesmaids bought all that tat for mine but the best best thing (it's so good I had to say best twice !) was a hen night style guest book . They passed it around and everyone wrote a message in it and the drunk ones are absolutely amazing !! It's to this day one of my prized possessions !!